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SMTP server for Linux with simple configuration
I'm looking for a simple SMTP server that I can run without too much installation hastle and that which can also support TLS.
These are too few requirements that have to be fulfilled. But the one and only answer to that question is Postfix. It's the only server - that I know of - which ships with a working and secure preconfiguration.
Postfix and others are simple. This is what the S in SMTP stands for. And I don't know of any aspect of SMTP that Postfix can't do.